1. Field of the Invention
This invention generally relates to optical cables and, more particularly, to a fiber optical cable interface with a misalignment compensation mechanism.
2. Description of the Related Art
Conventionally, optical fiber connectors are spring-loaded. The fiber endfaces (optical interfaces) of the two connectors are pressed together, resulting in a direct glass to glass or plastic to plastic, contact. The avoidance of glass-to-air or plastic-to-air interfaces is critical, as an air interface results in higher connector losses. However, the tight tolerances needed to eliminate an air interface make these connectors relatively expensive to manufacture.
FIG. 1 is a partial cross-sectional view of a Transmission Optical SubAssembly (TOSA) optical cable plug (prior art). The plug 100 is made from a plastic housing 102 with a bored ferrule 106 to secure an optical fiber 108. The plug 100 also includes a plastic lens 110, manufactured as a subassembly, integrated into the plug. The lens 110 has a curved surface to create a focal plane where the plug mates with a jack 112. The lens permits a low loss air gap to be formed between the plug and a connecting jack. In addition to the expense of manufacturing a 2-part plug, the plug must be made to relatively tight tolerances, so that the lens focal plane aligns with the jack, which also increases the cost of the plug.
FIG. 2 is a partial cross-sectional view of an 8 Position 8 Contact (8P8C) interface (prior art). The ubiquitous 8P8C connector is a hardwired electrical connector used commercially and residentially to connect personal computers, printers, and routers. The 8P8C is often referred to as RJ45. Although the housing/body can be made as a one-piece plastic molding, the spring-loaded contacts and the necessity of cable crimping add to the complexity of manufacturing the part. Advantageously however, the spring-loaded contacts permit the part to be made to relatively lax tolerances.
It would be advantageous if an optical cable jack and plug could be made more inexpensively with a relaxed set of mechanical and optical tolerances.